Solid lipophilic composition and process for its preparation

ABSTRACT

The present invention relates to solid lipophilic compositions suitable for topical application to human skin and to methods for preparing and using such compositions. The solid lipophilic compositions of the invention comprise dibenzyl monosorbitol acetal (DBMSA), lipophilic materials and one or more cosmetic materials.

CROSS REFERENCE TO RELATED APPLICATION

This is a division of application Ser. No. 08/365,810, filed Dec. 29,1994 U.S. Pat. No. 5,610,199 entitled SOLID LIPOPHILIC COMPOSITION ANDPROCESS FOR ITS PREPARATION, which is a continuation-in-part ofapplicants' U.S. patent application Ser. No. 08/216,151, filed Mar. 22,1994 abandoned.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to solid, lipophilic compositions suitablefor topical application to human skin. In particular the inventionrelates to solid lipophilic compositions comprising dibenzylmonosorbitol acetal (DBMSA), lipophilic materials and one or morecosmetic materials.

The invention further relates to methods for preparing and using thecompositions.

BACKGROUND OF THE INVENTION

Dibenzyl monosorbitol acetal, herein referred to as DBMSA is a knowngelling agent. For example, DBMSA has been used as a gelling agent intransparent or translucent deodorant and antiperspirant sticks.

See, for example, U.S. Pat. Nos. 4,154,816, 4,346,079, 4,518,582,4,725,430, 4,743,444, 4,816,261, and 4,781,917 and European patentapplications 260,030 and 451,002. Hydrophilic solvents, such as lowermonohydric alcohols, are typically used in such deodorant andantiperspirant sticks to solubilize the DBMSA at elevated temperatures.

The use of hydrophilic solvents to solubilize DBMSA in many compositionscontaining cosmetic colorants, fragrances, sunscreens or dermatologicagents poses a number of problems. Such solvents are generallyirritating and are undesirable in compositions for use on areas havingmucus membranes (e.g., the areas around the lips or eyes.) Furthermore,hydrophilic solvents are generally incompatible with lipophiliccolorants that are frequently found in cosmetic preparations. Inaddition, lower monohydric alcohols, such as ethanol, are incompatiblewith certain sun care and antiinflammatory agents because they adverselyeffect the skin protective qualities of these agents.

Stable cosmetic and dermatologic compositions have been prepared bymelting together one or more lipophilic waxes and the appropriatecosmetic or dermatologic agents. The lipophilic wax-containingcompositions are then transferred to suitable containers for cooling andsolidification. Frequently, however, the resulting compositionscontaining high levels of lipophilic waxes are perceived to beexcessively sticky or greasy upon application.

An object of the present invention is to provide stable, solidlipophilic compositions containing DBMSA, a lipophilic material and acosmetic material which are suitable for topical application to humanskin. It is a further object of this invention to provide stable, solidlipophilic compositions containing DBMSA, a lipophilic material and acosmetic material that are not perceived as being sticky or greasy. Afurther object of this invention is to provide stable, lipophiliccompositions containing DBMSA and hydroxyacid derivatives. An additionalobject of this invention is to provide methods for preparing suchcompositions. Yet a further object of this invention is to providemethods for applying color to human skin, for protecting human skin fromsunlight, and for treating dermatologic disorders such as dry skin,wrinkles, and blemished skin, using the lipophilic DBMSA basedcompositions of this invention.

SUMMARY OF THE INVENTION

The compositions of the present invention comprise:

(a) from about 1.5% by weight to about 30% by weight of DBMSA;

(b) from about 70% by weight to about 98.0% by weight of lipophilicmaterial; and

(c) from about 0.5% to about 28.5% by weight of a cosmetic materialselected from the group consisting of colorants, fragrances, sunscreens,dermatologic agents, and mixtures thereof.

The present invention also relates to methods for preparing suchcompositions, which comprise the steps of:

(a) mixing DBMSA with one or more lipophilic materials at a temperatureand for a period of time (e.g., about 15 min to about 45 min) sufficientto dissolve the DBMSA in the lipophilic material;

(b) mixing a cosmetic material selected from the group consisting ofcolorants, fragrances, sunscreens, dermatologic agents and mixturestherefore with the admixture of DBMSA and one or more lipophilicmaterials, the amounts of the materials being adjusted such that theresulting mixture contains from about 1.5% by weight to about 30% byweight DBMSA, from about 70% by weight to about 98.0% by weight oflipophilic material, and from about 0.5% by weight to about 28.5% byweight of cosmetic material; and

(c) cooling the mixture to ambient temperature.

It is to be understood that step (b) set forth above may be conductedprior to the DBMSA being dissolved in the lipophilic material, or duringor after the dissolution step. In other words, the cosmetic material maybe mixed with the other components of the mixture before or after theDBMSA is dissolved in the lipophilic material or while the dissolutionstep is being conducted. It will be understood further that the terms"mixture" and "mixing" in this application are used in the broad senseof the words with term "mixture" including, without limitation, blends,solutions, and suspensions.

The compositions of this invention are chemically and physically stable,nonirritating, and aesthetically pleasing. The compositions of thisinvention may comprise hydroxyacid derivatives which decompose in anaqueous environment to release products that are beneficial to the skin.In addition, the compositions of the invention may be made to besubstantially non-greasy and non-sticky by utilizing lipophilic oils asthe only or primary lipophilic material in the composition. Preferably,at least 80% by weight of the lipophilic material is a lipophilic oil(as opposed to a lipophilic wax) to achieve a composition that issubstantially non-greasy and non-sticky.

DETAILED DESCRIPTION OF THE INVENTION

The compositions described herein comprise from about 1.5% by weight toabout 30% by weight DBMSA. Preferably the compositions comprise about2.0% by weight to about 5.0% by weight DBMSA. DBMSA suitable for use inthe invention may be obtained from a number of commercial sources. Amongthe commercially available sources of DBMSA are MILLITHIX™ 925 (obtainedfrom Milliken Chemical, a division of Milliken & Company, Spartansburg,S.C.), GELL-All-D™ (obtained from New Japan Chemical Company; Ltd.), andDISORBENE™ (obtained from ROQUETTE Freres, France.)

The concentration of DBMSA in a particular composition influences thehardness and clarity of the composition, as well as the level of producttransfer to the skin upon application. Appropriate concentrations can bereadily determined by one of skill in the art, and will vary dependingon the solubility of the DBMSA in the composition. In general, anincrease in the concentration of DBMSA will provide a harder, lesstransparent composition, and a lower level of product transfer to theskin upon application. Conversely, a decrease in the concentration ofDBMSA will provide a softer, more transparent composition, and a higherlevel of product transfer to the skin upon application.

The compositions of this invention also comprise from about 70% byweight to about 98.0% by weight of a lipophilic material. Lipophilicmaterial, as used herein, refers to a non-polar material that ismiscible in lipids. One class of lipophilic materials that may be usedin the invention is lipophilic material from the class of materialsknown as cosmetically acceptable esters, e.g., mono-, di- and tri-estershaving an alcohol chain length of 1 to 22 and an acid chain length of 1to 22. Persons skilled in the art recognize that the group ofcosmetically acceptable esters is very large, and can be furthersubdivided into, e.g., oils, waxes, glyceryl esters aliphatic esters andfats. See, e.g., CFTA International Cosmetic Ingredient Dictionary, 4thed. (J. M. Nikitakis, et al. eds. Cosmetic, Toiletry and FragranceAssociation, Inc. Washington, 1991).

Preferably at least about 80% by weight, most preferably at least about95% by weight of the lipophilic material is one or more lipophilic oils.As used herein, the term lipophilic oils, refers to lipophilic materialsthat are liquid at room temperature about 17° C. to about 25° C.Preferred lipophilic oils for use in the invention are selected from thegroup consisting of castor oil, mineral oil, squalene, fatty acids(e.g., oleic acid), fatty alcohols (e.g., octyldodecanol), C₁₂₋₁₅ alkylbenzoate, propylene glycol dipelargonate, glycerol trioctanoate andmixtures thereof.

The lipophilic material may also be a lipophilic wax. Preferably, lessthan about 20% by weight of the lipophilic material is one or morelipophilic waxes, particularly where non-greasy and non-stickycompositions are desired. As used herein, the term lipophilic waxes,refers to lipophilic materials that are solid at room temperature, butmelt at elevated temperatures. Preferred lipophilic waxes are thoseselected from the group consisting of insect waxes, such as beeswax,animal waxes, such as lanolin, plant waxes, such as carnauba, mineralwaxes, such as ozokerite, petroleum waxes, such as paraffin wax,synthetic waxes, such as polyethylene, and mixtures thereof.

The specific composition and amount of the lipophilic material that isused for a particular composition is a function of the aesthetic andfunctional properties desired for that composition. The aesthetic andfunctional properties that may be controlled by a person skilled in theart by varying the composition and amount of lipophilic material used inthe composition of the invention include, for example, emolliency, skinfeel, and rate of absorbance through the skin.

The compositions of this invention also comprise from about 0.5% byweight to about 28.5% by weight of a cosmetic material chosen from thegroup consisting of colorants, fragrances, and sunscreens anddermatological agents and mixtures thereof. Colorants useful in thecomposition of the invention include lipophilic dyes, lakes, pigmentsand mixtures thereof. Preferred fragrances are the essential oils.Dermatological agents that may be used in our compositions includevitamins, antiinflammatory agents, hydroxyacids, hydroxyacidderivatives, and the like, and mixtures thereof.

Hydroxyacid derivatives that are useful in this invention include cyclicesters of a hydroxycarboxylic acid having the chemical formula: ##STR1##wherein R₁ and R₂ may be the same or different. R₁ and R₂ may beselected from the group comprising hydrogen, alkyl, aralkyl or arylgroup of saturated or unsaturated, isomeric or non-isomeric, straightchain, branched chain or cyclic form, having 1-25 carbon atoms.Preferably R₁ and R₂ are selected from the group consisting of hydrogen,methyl, ethyl, propyl, isopropyl, butyl, benzyl, and phenyl. Morepreferably R₁ and R₂ are selected for the group consisting of hydrogenand methyl. R₃ and R₄ may be selected independently from the groupcomprising hydrogen, a halogen atom and a radical, such as, a loweralkyl, aralkyl, aryl or alkoxy of saturated or unsaturated, isomeric ornon-isomeric, straight or branched chain or cyclic form, having 1-9carbon atoms. Preferably R₃ and R₄ are hydrogen. The most preferredhydroxyacid derivatives of this invention are lactide(3,6-dimethyl-1,4-dioxane-2,5-dione) and glycolide(1,4-dioxane-2,5-dione).

It is believed that the hydroxyacid derivatives useful in the preferredcompositions of the invention break down over time into hydroxyacidsupon application to and continued contact with the skin. It is believedthat this sustained release of the hydroxyacids over time impartsbeneficial effects to the skin.

Sunscreens that may be used include dioxybenzone, 2-ethylhexyl2-cyano-3,3 diphenylacrylate, 2-ethylhexyl p-methoxycinnamate,2-ethylhexyl salicylate, homosalate, menthyl anthranilate, oxybenzone,octyl dimethyl PABA, red petrolatum, titanium dioxide, ferulic acidesters, or mixtures thereof. Preferably the sunscreen is titaniumdioxide, ferulic acid esters or mixtures thereof. Most preferably thesunscreen is titanium dioxide or ethyl ferulate or mixtures thereof.

The compositions of this invention may also comprise other ingredientsthat are commonly employed by one of skill in the art in compositionsfor application to the skin (e.g., stabilizers, antimicrobial agents,antioxidants, and the like).

In the method of the present invention, DBMSA, a lipophilic material anda cosmetic material are combined at a temperature and a period of timesufficient to dissolve substantially all of the DBMSA in the lipophilicmaterial to obtain a solution of DBMSA in the liquid material. Thesolution is then solidified by cooling it.

The DBMSA, lipophilic materials and cosmetic materials may be combinedand mixed together using any means familiar to those skilled in the art.For example, a LIGHTNIN™ Stirrer or a Silverson homogenizer may be usedfor this purpose.

The heating step is carefully monitored (e.g., by visual means) toensure that the solution is substantially free of undissolved DBMSA.

In a preferred embodiment of this invention, the DBMSA and thelipophilic material are combined and heated at a temperature sufficientto dissolve substantially all the DBMSA before one or more cosmeticmaterials are added to the mixture. Preferably, the temperature is about75° C. to about 200° C. Most preferably the temperature is about 150° C.to about 200° C. Once substantially all the DBMSA is in solution, thecosmetic material is admixed with the mixture and the resultingadmixture is cooled to room temperature. Particularly when the cosmeticmaterial is colored or particulate, proceeding in this mannerfacilitates the ability of the person(s) making the composition todetermine that substantially all the DBMSA is dissolved in thelipophilic material.

Preferably, the heated mixture is transferred while still above ambienttemperature to the container in which it will be stored, where it issolidified. For example, the heated, still liquid material may betransferred to a lipstick mold, a makeup pan, or a wide-mouthed jar andcooled to about ambient temperature to solidify the mixture.

The compositions of the present invention may be formulated for a widerange of cosmetic applications. For example, the compositions may beformulated as lip area treatment preparations, eye area treatmentpreparations, sunscreen preparations, antiinflammatory preparations,antiacne preparations, antibacterial preparations, color cosmeticpreparations, fragrance preparations, moisturizing preparations,exfoliating preparations, and the like.

The following non-limiting examples illustrate various compositions ofthe present invention.

EXAMPLES Example 1

    ______________________________________                                        Transparent Lipstick                                                          Component          Parts By Weight                                            ______________________________________                                        Phase 1:                                                                      Finsolv TN.sup.1   48.25                                                      Trivent OC-G.sup.2 48.25                                                      DBMSA              3.00                                                       Phase 2:                                                                      D&C Red No. 21 6921/362.sup.3                                                                    0.50                                                       ______________________________________                                         .sup.1 A C.sub.12-15 alkyl benzoatecontaining composition obtained from       Finetex, Inc.                                                                 .sup.2 A glycerol trioctanoatecontaining composition obtained from Triven     Chemical Co.                                                                  .sup.3 A D&C Red No. 21containing composition obtained from Sun Chemical      Corp.                                                                    

Procedure

Phase 1 was blended at 175° C. using a LIGHTNIN™ Mixer until a clearsolution was obtained. Phase 2 was then mixed into this solution. Theresultant mixture was poured into a lipstick mold and cooled to roomtemperature.

The procedure of Example 1 was also used to prepare the compositions ofExamples 2-4.

Example 2

    ______________________________________                                        A Low-Wax Lipstick                                                            Component         Parts By Weight                                             ______________________________________                                        Phase 1:                                                                      Emerest 2388.sup.4                                                                              39.00                                                       Castor Oil USP/Crystal O.sup.5                                                                  34.00                                                       Lantrol (Plain).sup.6                                                                           5.00                                                        Beeswax - White S.P. 422.sup.7                                                                  5.00                                                        Panalane L-14E.sup.8                                                                            5.00                                                        DBMSA             4.00                                                        Phase 2:                                                                      Flamenco Superpearl.sup.9                                                                       1.00                                                        D&C Red No. 7     7.00                                                        Ca Lake 66O7/3l07.sup.10                                                      ______________________________________                                         .sup.4 A propylene glycol dipelargonatecontaining composition obtained        from Henkel Corp.                                                             .sup.5 A castor oilcontaining composition obtained from Caschem, Inc.         .sup.6 A lanolin oilcontaining composition obtained from Henkel Corp.         .sup.7 A beeswaxcontaining composition obtained from Strahl & Pitsch.         .sup.8 A polybutenecontaining composition obtained from Amoco Chemicals.      .sup.9 A mica/titanium dioxidecontaining composition obtained from Mearl      Corp.                                                                         .sup.10 A mixture composed of 30 parts by weight D&C Red No. 7 Calcium        Lakecontaining composition (obtained from HiltonDavis Chemical Co.), and      70 parts by weight Castor Oil USP/Crystal O. The mixture is combined in a     stainless steel mixing container and blended with a Hockmeyer high energy     disperser. The mixture is then passed through a threeroller mill twice        until a "fineness of grind" reading of greater that 7 on the North scale      of a Hegman gauge is obtained.                                           

The composition of Example 2 is useful for providing an aestheticallypleasing, non-sticky, non-greasy transfer of color to the lip area.

Example 3

    ______________________________________                                        A Sunscreen Stick                                                             Component      Parts By Weight                                                ______________________________________                                        Phase 1:                                                                      Finsolv TN     87.00                                                          DBMSA          3.00                                                           Phase 2:                                                                      Ethyl Ferulate.sup.11                                                                        5.00                                                           Tioviel FIN.sup.12                                                                           5.00                                                           ______________________________________                                         .sup.11 An ethyl ferulatecontaining composition obtained from ICN             Biochemicals, Irvine, CA.                                                     .sup.12 An ultra fine titanium dioxidecontaining composition (40% by          weight in an C.sub.12-15 Alkyl Benzoate) obtained from Tioxide Specialtie     Ltd.                                                                     

This composition provided a Sun Protection Factor (SPF) of approximately16.8, as measured by the in vivo method (See: "Sunscreen Products forOver-The-Counter Human Drugs, Proposed Safety, Effective and LabelingConditions", Department of Health, Education, and Welfare, Food and DrugAdmin., Federal Register 43(166), Part II, pp. 38206-38269 (1978)).

Example 4

    ______________________________________                                        An Exfoliating Preparation                                                    Component          Parts By Weight                                            ______________________________________                                        Phase 1:                                                                      Finsolv TN         44.50                                                      Castor Oil USP/Crystal O                                                                         44.50                                                      DBMSA              3.00                                                       Phase 2:                                                                      Salicylic Acid USP (Powder).sup.13                                                               2.00                                                       Silicone 200 Fluid - 500 Cts.sup.14                                                              5.00                                                       Vitamin E/Linoleate.sup.15                                                                       1.00                                                       ______________________________________                                         .sup.13 A salicylic acidcontaining composition obtained from RhonePoulenc     Inc.                                                                          .sup.14 A dimethiconecontaining composition obtained from Dow Corning         Corp.                                                                         .sup.15 A tocopheryl linoleatecontaining composition obtained from Roche      Products Ltd.                                                            

Example 5

    ______________________________________                                        A Facial Makeup                                                               Component          Parts By Weight                                            ______________________________________                                        Phase 1:                                                                      Castor Oil USP/Crystal O                                                                         4.03                                                       FD&C Yellow No. 5  O.64                                                       Al Lake B3014.sup.16                                                          D&C Red No. 6      0.50                                                       Lake C19-022.sup.17                                                           D&C Red No. 7      0.38                                                       Lake C19-011.sup.18                                                           FD&C Blue No. 1    0.01                                                       Al Lake (Lakoline).sup.19                                                     Pure Oxy Red 7054/3080.sup.20                                                                    0.36                                                       Titanium Dioxide 328 USP.sup.21                                                                  1.08                                                       Phase 2:                                                                      Schercemol DIS.sup.22                                                                            63.00                                                      Ceraphyl 791.sup.23                                                                              11.00                                                      DBMSA              4.00                                                       Phase 3:                                                                      Mica 280 BC.sup.24 10.00                                                      Speron P-1500.sup.25                                                                             5.00                                                       ______________________________________                                         .sup.16 A FD&C Yellow No. 5 (Aluminum Lake)containing composition obtaine     from WarnerJenkinson Cosmetic Colors.                                         .sup.17 A D&C Red No. 6 (Barium Lake)containing composition obtained from     Sun Chemical Corp.                                                            .sup.18 A D&C Red No. 7 (Calcium Lake)containing composition obtained fro     Sun Chemical Corp.                                                            .sup.19 A FD&C Blue No. 1 (Aluminum Lake)containing composition, obtained     from WarnerJenkinson Cosmetic Colors.                                         .sup.20 An iron oxidescontaining composition obtained from WarnerJenkinso     Cosmetics Colors.                                                             .sup.21 A titanium dioxidecontaining composition obtained from Sun            Chemical Corp.                                                                .sup.22 A diisopropyl sebacatecontaining composition obtained from Scher      Chemicals, Inc.                                                               .sup.23 An isocetyl stearoyl stearatecontaining composition obtained from     ISP Van Dyk Inc.                                                              .sup.24 A micacontaining composition obtained from WarnerJenkinson            Cosmetic Colors.                                                              .sup.25 A silicacontaining composition obtained from Presperse Inc.      

Procedure

Phase 1 was blended in a three-roller mill until it was homogenous.Phase 2 was heated at 175° C. until a clear solution was obtained.Phases 1 and 3 were then added to the phase 2 solution and the resultantmixture was poured into a makeup pan and cooled to room temperature.

Example 6

    ______________________________________                                        A Solid Fragrance Stick                                                       Component      Parts by Weight                                                ______________________________________                                        Phase 1:                                                                      Emerest 2388   92.00                                                          DBMSA          3.00                                                           Fragrance      5.00                                                           ______________________________________                                    

Phase 1 was blended at 175° C. using a LIGHTNIN™ Mixer until a clearsolution was obtained. The solution was poured into a mold and cooled toroom temperature.

Example 7

    ______________________________________                                        Transparent Skin Treatment Stick                                              Component    Parts by Weight                                                  ______________________________________                                        Phase 1:                                                                      Finsolv TN   96.00                                                            DBMSA        3.00                                                             Phase 2:                                                                      Lactide.sup.26                                                                             1.00                                                             ______________________________________                                         .sup.26 A lactidecontaining composition obtained from Aldrich Chemical Co                                                                              

Procedure

Phase 1 was heated, with stirring, to 180°-185° C. or until the DBMSAwas dissolved and a clear solution was obtained. Phase 2 was then mixedinto this solution. The resultant mixture was poured into a mold andcooled to room temperature.

While the present invention has been set forth in terms of specificembodiments thereof, it will be understood that the invention is definedby the appended claims.

We claim:
 1. A method for preparing a solid lipophilic compositioncomprising the steps of:(a) mixing DBMSA with one or more lipophilicmaterials at a temperature and for a period of time sufficient todissolve the DBMSA in the lipophilic material; (b) mixing a cosmeticmaterial selected from the group consisting of colorants, fragrances,sunscreens, dermatologic agents and mixtures therefore with theadmixture of DBMSA and one or more lipophilic materials, the amounts ofthe materials being adjusted such that the resulting mixture containsfrom about 1.5% by weight to about 30% by weight DBMSA, from about 70%by weight to about 98.0% by weight of lipophilic material, and fromabout 0.5% by weight to about 28.5% by weight of cosmetic material; and(c) cooling the mixture to ambient temperature.
 2. The method accordingto claim 1, wherein the temperature in step (a) is about 75° C. to about200° C.
 3. The method according to claim 1, wherein step (b) isconducted prior to, during or after the DBMSA is dissolved in thelipophilic material.
 4. The method according to claim 1, wherein theDBMSA is dissolved in the lipophilic material before step(b) isconducted.
 5. A composition prepared according to the method of claims1, 2, 3, or
 4. 6. A method for applying a cosmetic composition to theskin comprising the step of applying to the skin the composition ofclaim 5.